Test System with Test Trays and Automated Test Tray Handling

ABSTRACT

A test system may be provided in which devices under test are loaded into test trays. Each test tray may include clamps for retaining a device under test within the test tray. The test tray may be configured to transmit test tray identification information to facilitate tracking of the device under test associated with the test tray. The test tray may include engagement features configured to receive corresponding engagement features on a computer-controlled loading arm. The loading arm may be used to move the test tray and associated device under test to a test fixture for testing. A contact extending structure may be retained in the test tray and may be configured to mate with the device under test. Contact pads on the contact extending structure may be mated with corresponding contacts on the test fixture to form an electrical connection between the device under test and the test fixture.

This application claims the benefit of provisional patent applicationNo. 61/595,572, filed Feb. 6, 2012, which is hereby incorporated byreference herein in its entirety.

BACKGROUND

This relates generally to automation, and more particularly, toautomated equipment for use in manufacturing operations such as testing.

Electronic devices are often tested following assembly to ensure thatdevice performance meets design specifications. For example, a devicemay be tested at a series of test stations to ensure that components andsoftware in the device are operating satisfactorily. At each teststation, an operator may couple a device to test equipment using acable. Following successful testing at all test stations, a device maybe shipped to an end user.

The process of attaching and detaching test cable connectors can reducethe lifetime of the test cable connectors and can be cumbersome andburdensome to test system operators. If care is not taken, tests may beless accurate and more time consuming than desired. Additionally,excessive contact between a test system operator and a device under testmay increase the risk of cosmetic damage to the device under test.

It would therefore be desirable to be able to provide improved ways ofperforming manufacturing operations such as testing operations onelectronic devices.

SUMMARY

A test system may be provided in which devices under test are loadedinto test trays. Each test tray may include one or more spring-loadedmembers for retaining a device under test within the test tray.

A test tray may include a base portion having an opening and one or moreside walls having an opening. Openings may be configured to align withinput-output devices in the device under test when the device under testis installed in the test tray.

A test tray may be provided with engagement holes configured to receivecorresponding engagement pins on a computer-controlled loading arm. Theloading arm may engage with the test tray by inserting the engagementpins into the engagement holes. Once engaged, the loading arm may beused to pick up, hold, and transport the device under test to a desiredlocation in the test system.

The test system may be a conveyor belt system in which test stations arelocated along a moving conveyor belt. The test trays and associateddevices under test may be fed into the conveyor belt system for testingat the test stations. Each test station may be provided with one or moreloading mechanisms. A sensor may be used to detect when a test tray andassociated device under test has reached a predetermined location in theconveyor belt system. In response to detecting a test tray at apredetermined location, a computer-controlled loading arm may beactuated to pick up the test tray from the conveyor belt and to bringthe test tray and associated device under test to a test station fortesting.

A contact extending structure may be used to form an electricalconnection between a device under test in a test tray and a test fixtureat a test station. A slot may be formed in the test tray and may be usedto retain the contact extending structure within the test tray. Thecontact extending structure may have a first end configured to mate withthe electronic device and a second end having contact pads. The contactpads may be configured to mate with corresponding test fixture contactsat a test station.

A computer-controlled loading arm may install a test tray and associateddevice under test in a test fixture for testing by mating the contactson the contact extending structure with the test fixture contacts at thetest station. The contact extending structure may be used to convey testsignals between the test fixture and the device under test.

Each test tray may be provided with a radio-frequency identification tagfor transmitting test tray identification information. One or moresensors in the test system may be configured to receive the test trayidentification information and to identify the test tray based on thereceived test tray identification information. The test trayidentification information may be used to determine information aboutthe device under test associated with each test tray.

Further features of the invention, its nature and various advantageswill be more apparent from the accompanying drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an illustrative electronic device suchas a handheld device of the type that may be manufactured usingautomated equipment in accordance with an embodiment of the presentinvention.

FIG. 2 is a perspective view of an illustrative electronic device suchas a tablet computer of the type that may be manufactured usingautomated equipment in accordance with an embodiment of the presentinvention.

FIG. 3 is a schematic diagram of an illustrative electronic device withinput/output devices and wireless communications circuitry in accordancewith an embodiment of the present invention.

FIG. 4 is a diagram of manufacturing equipment of the type that may beused in manufacturing an electronic device in accordance with anembodiment of the present invention.

FIG. 5 is an exploded perspective view of an illustrative device undertest, pad extender, and test tray in accordance with an embodiment ofthe present invention.

FIG. 6 is a perspective view of an illustrative device under test, padextender, and test tray in accordance with an embodiment of the presentinvention.

FIG. 7 is a top perspective view of an illustrative test tray inaccordance with an embodiment of the present invention.

FIG. 8 is a bottom perspective view of an illustrative test tray inaccordance with an embodiment of the present invention.

FIG. 9 is a bottom perspective view of an illustrative test tray with anopening to accommodate tests in accordance with an embodiment of thepresent invention.

FIG. 10 is a rear perspective view of an illustrative pad extender forextending contacts in a device under test mounted in a test tray inaccordance with an embodiment of the present invention.

FIG. 11 is a front perspective view of an illustrative pad extender forextending contacts in a device under test mounted in a test tray inaccordance with an embodiment of the present invention.

FIG. 12 is a perspective view of an illustrative test tray in which adevice under test has been mounted in accordance with an embodiment ofthe present invention.

FIG. 13 is a perspective view of a portion of a test tray having clampsthat hold a device under test in accordance with an embodiment of thepresent invention.

FIG. 14 is a top view of an illustrative test tray having spring-loadedclamps for retaining devices under test in accordance with an embodimentof the present invention.

FIG. 15 is a top view of an illustrative test system in whichcomputer-controlled loading arms are used to transfer test trays betweentest stations and a conveyor belt in accordance with an embodiment ofthe present invention.

FIG. 16 is an exploded perspective view of an illustrative test fixturehaving test fixture contacts that mate with corresponding contacts on apad extender in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

Electronic devices such as electronic device 10 of FIG. 1 may bemanufactured using automated manufacturing equipment. The automatedmanufacturing equipment may include equipment for assembling devicecomponents together to form an electronic device. The automatedmanufacturing equipment may also include testing systems for evaluatingwhether devices have been properly assembled and are functioningproperly.

Devices such as device 10 of FIG. 1 may be assembled and tested using anautomated manufacturing system. The manufacturing system may include oneor more stations such as one or more test stations for performingtesting operations.

Devices that are being tested in a test system may sometimes be referredto as devices under test (DUTs). Devices under test may be provided tothe test stations using a conveyor belt, using robotic arms, and/orusing other loading equipment.

Test equipment at each test station may be used to perform an associatedtest on a device. For example, one test station may have equipment fortesting a display in the device. Another test station may have equipmentfor testing an audio component in the device. Yet another test stationmay have equipment for testing light sensors in the device. Yet anothertest station may have equipment for testing wireless communicationscircuitry in the device. Automated equipment in the test system may beused in loading and unloading devices under test, in conveying devicesunder test between test stations, and in performing tests andmaintaining a database of test results.

Any suitable device may be tested using test equipment. As an example,device 10 of FIG. 1 may be tested using test equipment. Device 10 may bea computer monitor with an integrated computer, a desktop computer, atelevision, a notebook computer, other portable electronic equipmentsuch as a cellular telephone, a tablet computer, a media player, awrist-watch device, a pendant device, an earpiece device, other compactportable devices, or other electronic equipment. In the configurationshown in FIG. 1, device 10 is a handheld electronic device such as acellular telephone, media player, navigation system device, or gamingdevice.

As shown in FIG. 1, device 10 may include a housing such as housing 12.Housing 12, which may sometimes be referred to as a case, may be formedof plastic, glass, ceramics, fiber composites, metal (e.g., stainlesssteel, aluminum, etc.), other suitable materials, or a combination ofthese materials. In some situations, parts of housing 12 may be formedfrom dielectric or other low-conductivity material. In other situations,housing 12 or at least some of the structures that make up housing 12may be formed from metal elements.

Device 10 may, if desired, have a display such as display 14. Display 14may be a touch screen that incorporates capacitive touch electrodes ormay be insensitive to touch. Display 14 may include image pixels formedfrom light-emitting diodes (LEDs), organic light-emitting diodes(OLEDs), plasma cells, electrophoretic display elements, electrowettingdisplay elements, liquid crystal display (LCD) components, or othersuitable image pixel structures. A cover glass layer may cover thesurface of display 14. Openings for buttons such as button 20, openingsfor speaker ports such as speaker port 22, and other openings may beformed in the cover layer of display 14, if desired.

The central portion of display 14 (i.e., active region 16) may includeactive image pixel structures. The surrounding rectangular ring-shapedinactive region (region 18) may be devoid of active image pixelstructures. If desired, the width of inactive region 18 may be minimized(e.g., to produce a borderless display).

Device 10 may include components such as front-facing camera 24. Camera24 may be oriented to acquire images of a user during operation ofdevice 10. Device 10 may also include a rear facing camera. A rearfacing camera may be formed on a back side of device 10 (e.g., on anopposing side of display 14).

Device 10 may include sensors in portion 26 of inactive region 18. Thesesensors may include, for example, an infrared-light-based proximitysensor that includes an infrared-light emitter and a corresponding lightdetector to emit and detect reflected light from nearby objects. Thesensors in portion 26 may also include an ambient light sensor fordetecting the amount of light that is in the ambient environment fordevice 10. Other types of sensors may be used in device 10 if desired.The example of FIG. 1 is merely illustrative.

Device 10 may include input-output ports such as port 28. Ports such asport 28 may include audio input-output ports, analog input-output ports,digital data input-output ports, or other ports. Each port may have anassociated connector. For example, an audio port may have an associatedfour-contact audio connector, a digital data port may have a connectorwith two or more pins (contacts), a connector with four or more pins, aconnector with thirty pins, or other suitable data port connector.

Sensors such as the sensors associated with region 26 of FIG. 1, camerassuch as camera 24, audio ports such as speaker port 22, buttons such asbutton 20, and ports such as port 28 may be located on any suitableportion of device housing 12 (e.g., a front housing face such as adisplay cover glass portion, a rear housing face such as a rear planarhousing wall, sidewall structures, etc.).

FIG. 2 is a perspective view of device 10 in an illustrativeconfiguration in which device 10 has been implemented in the form of atablet computer. As shown in FIG. 2, device 10 may include a housingsuch as housing 12. Housing 12 may be formed from metal, plastic,fiber-based composite material, glass, ceramic, other materials, orcombinations of these materials. Device 10 may have an upper (front)surface that is covered with display 14. Active portion 16 of display 14may have a rectangular shape (as an example). Inactive portion 18 ofdisplay 14 may have an opening to accommodate button 20, a window regionfor camera 24, and a portion such as portion 26 that is associated withone or more optical sensors such as an infrared-based proximity sensorand/or an ambient light sensor.

A schematic diagram of an electronic device such as electronic device 10is shown in FIG. 3. As shown in FIG. 3, electronic device 10 may includestorage and processing circuitry 27. Storage and processing circuitry 27may include storage such as hard disk drive storage, nonvolatile memory(e.g., flash memory or other electrically-programmable-read-only memoryconfigured to form a solid state drive), volatile memory (e.g., staticor dynamic random-access-memory), etc. Processing circuitry may be basedon one or more microprocessors, microcontrollers, digital signalprocessors, baseband processors, power management units, audio codecchips, application specific integrated circuits, etc.

Storage and processing circuitry 27 may be used to run software ondevice 10, such as internet browsing applications,voice-over-internet-protocol (VoIP) telephone call applications, emailapplications, media playback applications, operating system functions,etc. To support interactions with external equipment, storage andprocessing circuitry 27 may be used in implementing communicationsprotocols. Communications protocols that may be implemented usingstorage and processing circuitry 27 include internet protocols, wirelesslocal area network (WLAN) protocols (e.g., IEEE 802.11protocols—sometimes referred to as WiFi®), protocols for othershort-range wireless communications links such as the Bluetooth®protocol, cellular telephone protocols, etc.

Circuitry 27 may be configured to implement control algorithms thatcontrol the use of antennas in device 10. For example, to supportantenna diversity schemes and MIMO schemes or beam forming or othermulti-antenna schemes, circuitry 27 may perform signal qualitymonitoring operations, sensor monitoring operations, and other datagathering operations and may, in response to the gathered data, controlwhich antenna structures within device 10 are being used to receive andprocess data. As an example, circuitry 27 may control which of two ormore antennas is being used to receive incoming radio-frequency signals,may control which of two or more antennas is being used to transmitradio-frequency signals, may control the process of routing incomingdata streams over two or more antennas in device 10 in parallel, etc.

Input/output circuitry 29 may be used to allow data to be supplied todevice 10 and to allow data to be provided from device 10 to externaldevices. Input/output circuitry 29 may include input/output devices 31.Input/output devices 31 may include touch screens, displays withouttouch sensor capabilities, buttons, joysticks, click wheels, scrollingwheels, touch pads, key pads, keyboards, microphones, speakers, tonegenerators, vibrators, cameras, sensors, light-emitting diodes and otherstatus indicators, light sources, audio jacks and other audio portcomponents, data ports, light sensors, motion sensors (accelerometers),capacitance sensors, proximity sensors, etc. A user can control theoperation of device 10 by supplying commands through input/outputdevices 31 and may receive status information and other output fromdevice 10 using the output resources of input/output devices 31.

Wireless communications circuitry 33 may include radio-frequency (RF)transceiver circuitry formed from one or more integrated circuits, poweramplifier circuitry, low-noise input amplifiers, passive RF components,one or more antennas, transmission lines, and other circuitry forhandling RF wireless signals. Wireless signals can also be sent usinglight (e.g., using infrared communications).

Wireless communications circuitry 33 may include satellite navigationsystem receiver circuitry 35, transceiver circuitry such as transceivercircuitry 37 and 39, and antenna circuitry such as antenna circuitry 41.Satellite navigation system receiver circuitry 35 may be used to supportsatellite navigation services such as United States' Global PositioningSystem (GPS) (e.g., for receiving satellite positioning signals at 1575MHz) and/or other satellite navigation systems.

Transceiver circuitry 37 may handle 2.4 GHz and 5 GHz bands for WiFi®(IEEE 802.11) communications and may handle the 2.4 Bluetooth®communications band. Circuitry 37 may sometimes be referred to aswireless local area network (WLAN) transceiver circuitry (to supportWiFi® communications) and Bluetooth® transceiver circuitry. Circuitry 33may use cellular telephone transceiver circuitry (sometimes referred toas cellular radio) 39 for handling wireless communications in cellulartelephone bands such as bands at 850 MHz, 900 MHz, 1800 MHz, 1900 MHz,2100 MHz, and/or other cellular telephone bands of interest.

Examples of cellular telephone standards that may be supported bywireless circuitry 33 and device 10 include: the Global System forMobile Communications (GSM) “2G” cellular telephone standard, theEvolution-Data Optimized (EVDO) cellular telephone standard, the “3G”Universal Mobile Telecommunications System (UMTS) cellular telephonestandard, the “3G” Code Division Multiple Access 2000 (CDMA 2000)cellular telephone standard, and the “4G” Long Term Evolution (LTE)cellular telephone standard. Other cellular telephone standards may beused if desired. These cellular telephone standards are merelyillustrative.

Wireless communications circuitry 33 may include circuitry for othershort-range and long-range wireless links if desired. For example,wireless communications circuitry 33 may include wireless circuitry forreceiving radio and television signals, paging circuits, etc. In WiFi®and Bluetooth® links and other short-range wireless links, wirelesssignals are typically used to convey data over tens of hundreds of feet.In cellular telephone links and other long-range links, wireless signalsare typically used to convey data over thousands of feet or miles.

Wireless communications circuitry 33 may include one or more antennas41. Antennas 41 may be formed using any suitable antenna type. Forexample, antennas 41 may include antennas with resonating elements thatare formed from loop antenna structures, patch antenna structures,inverted-F antenna structures, slot antenna structures, planarinverted-F antenna structures, helical antenna structures, hybrids ofthese designs, etc. Different types of antennas may be used fordifferent bands and combinations of bands. For example, one type ofantenna may be used in forming a local wireless link antenna and anothertype of antenna may be used in forming a remote wireless link antenna.

FIG. 4 is a diagram of an illustrative system of the type that may beused for manufacturing operations such as device testing. As shown inFIG. 4, system 30 may include one or more stations such as test stations36. In general, test system 30 may include automated equipment that isused in loading and unloading devices under test, in conveying devicesunder test between test stations, and in performing tests andmaintaining a database of test results. Each test station 36 may, forexample, include test equipment 44 for performing one or more tests ondevice under test 10 and may therefore sometimes be referred to as adevice tester or DUT tester. For example, a first type of test station36 may have equipment for testing a display in device 10. A second typeof test station 36 may have equipment for testing an audio component indevice 10. Yet another type of test station 36 may have equipment fortesting light sensors in device 10. Yet another type of test station 36may have equipment for testing wireless communications circuitry indevice 10. If desired, test system 30 may include more than one teststation of the same type arranged along conveyor belt 38 so thatmultiple devices under test 10 can be tested in parallel.

Device under test 10 may, if desired, be installed in a test tray suchas tray 32. Tray 32 may be configured to receive one or more devicesunder test. For example, tray 32 may have multiple slots, each of whichis configured to receive a corresponding device under test. If desired,tray 32 may be configured to receive only a single device under test.

Device 10 may be installed in test tray 32 manually or using automatedequipment. To facilitate manual installation, test tray 32 may includefeatures to facilitate human manipulation. For example, test tray 32 mayinclude features that help an operator open and close clamps or otherdevice holding features in test tray 32.

Device under test 10 that is mounted in test tray 32 may be conveyedbetween test stations 36 using a conveyor belt such as conveyor belt 38(e.g., a belt that moves in direction 40). When using a conveyor systemsuch as one or more conveyor belts 38, each test station 36 may beprovided with loading mechanisms (e.g., one or more computer-controlledloaders) 46. With this type of arrangement, test tray 32 may serve as aninterface between device under test 10 and loader 46. Test tray 32 may,for example, be more robust than device 10, may have engagement featuresthat are configured to mate with loader 46, may have an identificationnumber that facilitates tracking, and may have other features thatfacilitate testing of device 10 by test stations 36.

For example, loader 46 in each test station 36 may be provided with oneor more computer-controlled positioning arms. The positioning arms inloader 46 may be used in picking up a test tray (i.e., a test tray thatis loaded with device under test 10) from conveyor 38 (arrow 50), may beused to present test tray 32 to tester 44 at test station 36 to performdesired testing on device under test 10, and may be used to replace testtray 32 on conveyor 38 following testing (arrow 52).

Test stations 36 may provide test results to computing equipment such astest host 42 (e.g., one or more networked computers) for processing.Test host 42 may maintain a database of test results, may be used insending test commands to test stations 36, may track individual traysand devices under test as the trays and devices pass through system 30,and may perform other control operations.

FIG. 5 is a diagram showing how device under test 10 may be receivedwithin test tray 32. As shown in FIG. 5, test tray 32 may have a basesuch as base 48 on which device under test 10 rests. Sidewalls such assidewalls 100 may be formed on peripheral portions of base 48, therebyforming a recess such as recess 154 in test tray 32. Device under test10 may be installed in test tray 32 by placing device under test 10within recess 154. Sidewalls 100 may be formed on one, two, three, orall four sides of device under test 10. Sidewalls 100 may contain devicelocating features such as tangential surfaces or notches and may havedevice retention structures such as clamps, clips, or other structures.

Device under test 10 may have one or more connector ports such as port28 (see, e.g., FIG. 1). A contact extending structure such as contactextending structure 144 may have a mating connector such as plug 146.Plug 146 may be configured to mate with a connector in port 28 whendevice under test 10 has been mounted in test tray 32 and when contactextending structure 144 (sometimes referred to as “pad extender” 144)has been moved towards device under test 10 in direction 148.

Following insertion of device under test 10 into test tray 32 andfollowing insertion of plug connector 146 of pad extender 144 intoconnector 28 of device under test 10, test tray 32 of FIG. 5 may appearas shown in FIG. 6. Pad extender 144 may contain signal paths thatconnect pins in connector 28 to corresponding contacts 62 on padextender 144. Contacts 62 may be configured to mate with correspondingcontacts coupled to tester 44 at test station 36 and/or test host 42during testing in system 30. If desired, pad extender 144 may beconfigured such that contacts 62 are flush with end surface 23 of testtray 32 when pad extender is connected to device under test 10 as shownin FIG. 6.

Because device under test 10 is connected to test contacts 62 in testtray 32 using pad extender 144 associated with test tray 32, it is notnecessary to repeatedly connect and disconnect device under test 10 fromcabling at each test station 36. Rather, connections between deviceunder test 10 and the test equipment at each test station 36 by may beformed by coupling contacts 62 in pad extender 144 to correspondingcontacts at each test station 36. By minimizing the number of times thatcables need to be connected and disconnected from each device undertest, the life of tester cables and connectors may be extended.

The use of test tray 32 may allow device under test 10 to be placedaccurately within test stations 36 (e.g., with an accuracy of +/−0.1 mmor better, as an example). Test tray 32 may shield device under test 10from scratches and other damage during testing. In general, device undertest 10 may be received within test tray 32 in either an upwards facingconfiguration in which display 14 faces outwards (e.g., in which display14 faces away from test tray 32) or in which display 14 faced downwards(e.g., in which display 14 faces towards test tray 32).

FIG. 7 is a perspective view of one suitable embodiment of test tray 32.As shown in FIG. 7, tray 32 may be provided with engagement featuressuch as holes 160. Engagement features such as holes 160 may be formedon one, two, three, or all four sides of test tray 32 and may beconfigured to mate with corresponding engagement features on automatedloading equipment such as loaders 46 at test stations 36 (FIG. 4). Forexample, holes 160 may be formed on opposing ends of test tray 32 suchas ends 32A and 32B of test tray 32. The example of FIG. 7 in whichengagement features 160 have been implemented in the form of holes ismerely illustrative. Engagement features 160 may be implemented in theform of slots, notches, dimples, openings, recesses, protrusions, orother features that allow test equipment such as computer-controlledloading equipment to engage with test tray 32.

Automated loading equipment such as loaders 46 may have engagement pinsthat are configured to engage simultaneously with ends 32A and 32B,allowing loader 46 to pick up, hold, and transport device 10 to adesired location (e.g., to a test station such as test station 36 ofFIG. 4). In the example of FIG. 7, test tray 32 is shown with fourengagement holes on each end. This is, however, merely illustrative. Ifdesired, tray 32 may include less than four engagement holes, more thanfour engagement holes, more than six engagement holes, more than 10engagement holes, etc.

Tray 32 may be formed using non-marring material such as acetyl plastic,Delrin® (a polyoxymethylene plastic), other plastics, or other suitablenon-marring materials. The use of non-marring materials may help avoidscratches or other damage to device under test 10 when device under test10 is placed within test tray 32. If desired, a layer of material 156may be formed on portions of test tray 32 such base portion 48. As anexample, material 156 may be formed using the same material that is usedto form tray 32. As another example, material 156 may be formed usingelastomeric material such as rubberized foam. Material 156 may, ingeneral, be formed using any suitable non-marring material.

Test tray 32 may be provided with guide structures configured toaccurately position device under test 10 in a desired location withinrecessed portion 154 of tray 32. As shown in FIG. 7, guide structuressuch as guide surfaces 150 may be used as reference points fordetermining the location of a device under test relative to test tray 32and/or test station 36. For example, a device under test may bepositioned in a known location relative to test tray 32 by registeringthe device under test against guide surfaces 150. A guide structure onthe end of tray 32 may have an exposed end guide surface such as guidesurface 150A. Guide structures on the side of tray 32 may have exposedside guide surfaces such as guide surfaces 150B. Guide surfaces such asguide surfaces 150A and 150B may sometimes be referred to as datums.

FIG. 8 is a bottom perspective view of one suitable embodiment of testtray 32. As shown in FIG. 8, holes, openings, or gaps such as gaps 80may be formed in sidewalls 100 of test tray 32. Gaps 80 in sidewalls 100may allow portions of device 10 to be untouched by test tray 32. Forexample, structures such as buttons, switches, ports (e.g., a subscriberidentity module (SIM) card port to authorize cellular telephoneservice), and other input/output devices may be formed in a housingsidewall of device 10. If desired, gaps 80 may be formed in portions ofsidewalls 100 that are adjacent to (e.g., aligned with) thesestructures. This type of configuration may ensure that structures suchas buttons or switches in device 10 are not unintentionally actuated orotherwise unnecessarily touched by test tray 32. This is, however,merely illustrative. If desired, sidewalls 100 of test tray 32 may befree of gaps.

Test tray 32 may have one or more openings in base 48 to facilitate testmeasurements on device under test 10 during testing. For example, asshown in the bottom perspective view of FIG. 9, openings such as opening82 may be formed in base 48 and may be configured to align with one ormore input-output devices in device under test 10 when device 10 isinstalled in tray 32. Test equipment at a test station may communicatewith a component in device 10 via opening 82. In the example of FIG. 9,opening 82 has an inverted cone shape to facilitate testing of a camerain device 10 (e.g., a light signal from a test light source may betransmitted through opening 82 to reach a camera in device 10, or alight-emitting diode flash from a camera in device 10 may emit lightthrough opening 82 to reach a light sensor at a test station). Otherexamples of components in device 10 that may be tested using openingssuch as opening 82 in test tray 32 include ambient light sensors,light-based proximity sensors, capacitive sensors, light-emitting diodes(e.g., for status indicators), display components, magnetic sensors, orother electrical components.

When device 10 is installed in test tray 32, some components in device10 may face away from test tray 32 (e.g., components formed on a frontside of device 10) and some components in device 10 may face towardstest tray 32 (e.g., components formed on a back side of device 10). Ifdesired, openings such as openings 82 may only be formed in portions ofbase 48 that are aligned with components in device 10 that face towardstest tray 32.

FIG. 10 is a perspective view of pad extender 144 showing how connector146 may protrude from one end of pad extender 144. FIG. 11 is aperspective view of pad extender 144 showing how contacts 62 may beformed on an opposing end of pad extender 144.

FIG. 12 is a perspective view of test tray 32 after device under test 10has been inserted into test tray 32. As shown in FIG. 12, test tray 32may have clamps 164 for holding device under test 10 within test tray32. The inner surfaces of clamps 164 may serve as guide surfaces 150(FIG. 7) or, if desired, may be separate structures adjacent to guidesurfaces 150.

Test tray 32 may have one or more notches or slots such as slot 170.Slot 170 may be configured to receive pad extender 144. If desired, padextender 144 may be retained within slot 170 when device 10 is installedin test tray 32 (e.g., when connector 146 of pad extender 144 isconnected to connector port 28 in device 10) and when device 10 is notinstalled in test tray 32 (e.g., when test tray 32 is empty).

FIG. 13 is a perspective view showing how clamps 164 may have portionsthat extend over a top surface of device under test 10. Clamps 164 maybe spring-loaded to facilitate installation of device under test 10 intest tray 32. For example, springs or other biasing structures may beused to bias the upper portions of clamps 164 towards device 10. When itis desired to load device 10 into test tray 32, clamps 164 may be pulledin direction 102 and device 10 may be placed on base 48. Followingplacement of device 10 on base 48, clamps 164 may be released and clamps164 may be forced towards device 10 (e.g., in direction 104) to securedevice 10 to test tray 32.

In addition to securing a device under test to a test tray, some clampsmay serve the additional purpose of accurately positioning a deviceunder test within a test tray. FIG. 14 is a top view of an illustrativetest tray in which spring-loaded members may be used to both secure andaccurately position a device under test within a test tray. As shown inFIG. 14, spring-loaded members such as spring-loaded corner clamp 174and spring-loaded side clamp 194 may be located at the periphery ofrecess 154 (e.g., may be mounted in sidewall portions 100 of FIG. 7).

Clamps such as corner clamp 174 may be located at one or more corners oftest tray 32 and may be used to accurately position a device under testwithin the test tray. For example, clamp 174 may be used to press device10 against alignment features in test tray 32 (e.g., may be used topress device 10 against two of three datums within test tray 32 such asguide surfaces 150). Corner clamp 174 may have a lip or protrudingportion such as portion 201 that extends partially over a top surface ofdevice 10 when device 10 is inserted in test tray 32. Clamp 174 may beconfigured to rotate about pivot point 172. A biasing structure such asspring 184 may be used to bias end portion 210 of clamp 174 in direction178 (e.g., away from recess 154). Because clamp 174 rotates about point172, the biasing force exerted on end portion 210 of clamp 174 may inturn provide a biasing force on opposing end portion 204 in direction182. When portion 210 of clamp 174 is pressed in direction 176, clamp174 will pivot about pivot point 172 and portion 204 of clamp 174 willmove outwards in direction 180 to accommodate insertion of device undertest 10 in recessed portion 154 of test tray 32. After inserting deviceunder test 10 into test tray 32, end portion 210 of clamp 174 may bereleased and corner portion 204 may be forced towards device 10 indirection 182.

Clamps such as side clamp 194 may be located on one or more sides oftest tray 32. If desired, clamp 194 may have a lip or protruding portionthat extends partially over a top surface of device 10 when device 10 isinserted in test tray 32. Side clamp 194 may pivot about pivot point188. A biasing structure such as spring 186 may be used to bias endportion 208 of clamp 194 in direction 196 (e.g., away from recess 154).Because clamp 194 rotates about pivot point 188, the biasing forceexerted on end portion 208 of clamp 194 may in turn provide a biasingforce on opposing end portion 206 of clamp 194 in direction 202. Whenportion 208 of clamp 194 is pressed in direction 192, clamp 194 willpivot about pivot point 188 and portion 206 of clamp 194 will moveoutwards in direction 198 to accommodate insertion of device under test10 in recessed portion 154 of test tray 32. After inserting device undertest 10 into test tray 32, portion 208 may be released and end portion206 may be forced towards device 10 in direction 202.

FIG. 15 is a top view of an illustrative conveyor belt 38 showing howtest trays 32 might be used in a test system such as conveyor beltsystem 30. Each test tray may contain a radio-frequency identification(RFID) tag such as tray ID tag 280 (e.g., a tag that wirelesslytransmits tray identification information such as a tray serial numberto RFID reading equipment). Conveyor belt system 30 may have one or morebuilt in sensors such as RFID reader 313 that may be used to monitorincoming test trays 32 for RFIDs. If the RFID reader at a test stationdetermines that the tray ID for a test tray matches previously receivedinstructions, the test station may initiate loading mechanisms (e.g.,loader 46) to load the test tray into the test station. The serialnumber or other identification information associated with test tray 32may be used in determining whether or not a device requires testing at agiven test station, may be used in determining whether or not a deviceunder test has successfully passed a given test, and/or may be used indetermining other information about a device that is installed in testtray 32.

One or more loaders 46 may be associated with each test station. Asshown in FIG. 15, loader 46 may include loading arm 306 and loading armpositioner 310. Positioner 310 may be a computer-controlled actuatorsuch as a motor-driven or air-driven actuator and may be configured tomove loading arm 306 along three axes (e.g., along X, Y, and Z axes).Loading arm 306 may have engagement arm members 306′. Each engagementarm member 306′ may have loading arm engagement features such asengagement pins 360 that are configured to mate with correspondingengagement holes 160 in test tray 32. Engagement arm members may becontrolled using air-driven or motor-drive actuators such as actuators308. Actuators 308 may be configured to move engagement arm members 306′in a direction that is parallel to axis Y.

Initially, device under test 10 and test tray 32 may be located on theleft hand side of conveyor belt 38. As conveyor belt 38 moves indirection 290, test tray 32 may approach location 312. A sensor such asRFID reader 313 may be positioned along conveyor belt 38 and may beconfigured to identify a serial number with test tray 32 as it passeslocation 312. Based on the identified serial number, test host 42 (FIG.4) may be used to determine whether or not the device under testassociated with that test tray needs to be tested at a given teststation. As test tray 32 approaches loader 46, a sensor such as sensor315 may be used to detect the presence of test tray 32 at location 314.Sensor 315 may (as an example) be a laser-based distance sensor. Ifdesired, a single sensor may be used to both detect and identify testtrays 32. The example of FIG. 15 in which separate sensors are used foridentification and detection of test tray 32 is merely illustrative.

In response to detection of test tray 32 by sensor 315, loading arm 306may automatically be moved by loading arm actuator 310 into the positionshown in FIG. 15. As conveyor belt 38 continues to move in direction290, device under test 10 and test tray 32 may be received withinloading arm 306. If desired, one or more sensors may be used to inform acontrolling computer such as host 42 (FIG. 4) when a test tray isproperly received within loading arm 306.

Engagement pins 360 (sometimes referred to as protrusions) may be usedto engage with test tray 32 so that loader arm 306 may pick up test tray32 from conveyor belt 38 and transfer test tray 32 to a desired location(e.g., test station 36). Initially, engagement pins 360 may be held in aretracted position by actuators 308. After conveyor belt 38 has movedtray 32 into a position within arm 306, actuators 308 may be used toextend pins 360 into holes 160. If desired, actuator 308 may beconfigured to move pins 360 towards test tray 32 by moving engagementarm members 306′ inward. The example in which actuator 308 moves onlyengagement pins 360 to engage with holes 160 is merely illustrative.Once loader arm 306 has engaged with test tray 32, loader arm 306 maydeliver test tray 32 and device under test 10 to a test fixture at thetest station associated with loader arm 306. In some configurations,loader arm 306 may unload test tray 32 at the test station bydisengaging pins 360 from holes 160. In other configurations, loader 306may remain engaged with test tray 32 while device under test 10 istested at a test station.

Following testing at a given test station, loading arm 306 may returntest tray 32 to conveyor belt 38. If desired, a first loading arm may beused in picking up test tray 32 from conveyor belt 38 and a secondloading arm may be used to return test tray 32 to conveyor belt 38. Testtray 32 may have a first and second sets of engagement holes 160 so thatfirst and second loading arms may simultaneously engage with test tray32 (e.g., so that test tray 32 may be transferred between loading arms).

Each test station 36 (FIG. 4) at which device under test 10 is testedmay have an associated test fixture configured to receive test tray 32and associated device under test 10. FIG. 16 is an exploded perspectiveview of test system 30 showing how test tray 32 may be received by atest fixture such as test fixture 34. After loading arm has 306 engagedwith test tray 32, loading arm 306 may present test tray 32 and deviceunder test 10 to test fixture 34 at a test station for testing. Testfixture 34 may have contacts such as test fixture contacts 134. Contacts134 (sometimes referred to as contact pads or contact pins) may beconfigured to mate with contacts 62 on pad extender 144. By bringing padextender contacts 62 into contact with test fixture contacts 134, anelectrical connection may be formed between device under test 10 andtest fixture 34. Test signals may be conveyed between test fixture 34and device under test 10 via pad extender 144.

Device under test 10 may be tested at multiple test stations. Ifdesired, each test station may have a test fixture with an associatedset of test fixture contacts 134. Pad extender 144 may be configured tomate with corresponding test fixture contacts 134 at each test station.

The foregoing is merely illustrative of the principles of this inventionand various modifications can be made by those skilled in the artwithout departing from the scope and spirit of the invention. Theforegoing embodiments may be implemented individually or in anycombination.

What is claimed is:
 1. Test apparatus for testing an electronic device,comprising: a test tray configured to receive the electronic device,wherein the test tray includes a plurality of test tray engagementfeatures configured to receive corresponding loader engagement featureson a computer-controlled loader; and a contact extending structurehaving first and second ends, wherein the first end comprises aconnector configured to mate with the electronic device, and wherein thesecond end comprises a plurality of contact pads configured to mate withcontacts at a test station.
 2. The test apparatus defined in claim 1,wherein the test tray further includes at least one spring-loaded memberconfigured to retain the electronic device within the test tray.
 3. Thetest apparatus defined in claim 1, wherein the test tray comprises abase and at least one side wall, wherein the at least one side wallcomprises at least one opening, and wherein the opening aligns with aninput-output device in the electronic device when the electronic deviceis received within the test tray.
 4. The test apparatus defined in claim1, wherein the test tray comprises a base and at least one side wall,wherein the base comprises at least one opening, and wherein the openingaligns with an input-output device in the electronic device when theelectronic device is received within the test tray.
 5. The testapparatus defined in claim 1, wherein the test tray comprises a slotconfigured to receive the contact extending structure.
 6. The testapparatus defined in claim 1, wherein the plurality of test trayengagement features comprises a plurality of recesses in the test tray.7. The test apparatus defined in claim 1, wherein the test traycomprises a radio-frequency identification tag configured to transmittest tray identification information.
 8. A test system for testing adevice under test, comprising: a test tray configured to receive thedevice under test, wherein the test tray comprises a radio-frequencyidentification tag configured to transmit test tray identificationinformation; a sensor configured to receive the test tray identificationinformation; a test fixture configured to receive the test tray; andcomputer-controlled loading equipment configured to engage with the testtray and to move the test tray towards the text fixture for testing. 9.The test system defined in claim 8, wherein the test fixture comprises aplurality of test fixture contacts, the test system further comprising:a contact extending structure having first and second ends, wherein thefirst end comprises a connector configured to mate with the device undertest and wherein the second end comprises a plurality of contact padsconfigured to mate with the plurality of test fixture contacts.
 10. Thetest system defined in claim 8, wherein the test tray comprises testtray engagement features, wherein the computer-controlled loadingequipment comprises a loading arm having loading arm engagementfeatures, and wherein the loading arm is configured to hold and move thetest tray by engaging the loading arm engagement features with the testtray engagement features.
 11. The test system defined in claim 8,wherein the test tray comprises a plurality of recesses, wherein thecomputer-controlled loading equipment comprises a loading arm having aplurality of protrusions, and wherein the loading arm is configured tohold and move the test tray by inserting each protrusion in theplurality of protrusions in an associated recess in the plurality ofrecesses.
 12. The test system defined in claim 8, wherein the test traycomprises at least one spring-loaded member configured to retain thedevice under test within the test tray.
 13. The test system defined inclaim 8, wherein the computer-controlled loading equipment comprises aloading arm and an actuator and wherein the actuator is configured toactuate the loading arm to engage with the test tray in response to thesensor receiving the test tray identification information.
 14. A methodof testing a device under test, comprising: installing the device undertest into a test tray; connecting a contact extending structure to aconnector port in the device under test; while the device under test isinstalled in the test tray and while the contact extending structure isconnected to the connector port, feeding the test tray into a conveyorbelt system; and with a computer-controlled loading arm, installing thetest tray in a test fixture for testing.
 15. The method defined in claim14, further comprising: with the test tray, transmitting test trayidentification information; and with a sensor, receiving the test trayidentification information.
 16. The method defined in claim 14, furthercomprising: with a sensor, detecting the test tray at a predeterminedlocation in the conveyor belt system; and in response to detecting thetest tray at the predetermined location, automatically actuating thecomputer-controlled loading arm to pick up the test tray.
 17. The methoddefined in claim 16, wherein the computer-controlled loading armcomprises a plurality of pins, wherein the test tray comprises aplurality of holes, and wherein automatically actuating thecomputer-controlled loading arm to pick up the test tray comprisesinserting each pin in the plurality of pins into an associated hole inthe plurality of holes.
 18. The method defined in claim 14 wherein thecontact extending structure comprises a plurality of contact pads,wherein the test fixture comprises a plurality of test fixture contacts,and wherein installing the test tray in the test fixture compriseselectrically connecting the plurality of contact pads to the pluralityof test fixture contacts.
 19. The method defined in claim 14, furthercomprising: after installing the test tray in the test fixture,performing testing on the device under test.
 20. The method defined inclaim 19, wherein performing testing on the device under test comprises:with the contact extending structure, conveying test signals between thetest fixture and the device under test.